Star formation in low brightness galaxies and in the extended gaseous disks of normal galaxies

Abstract

We analyze the available observational data on the radial distribution of gas and young stellar populations in the disks of low surface brightness (LSB) galaxies and in the outer regions or the extended disks of normal brightness (HSB) galaxies. These cases involve star formation under special conditions of low volume and surface gas density. There is no well-defined boundary between these subgroups of galaxies that we consider, but in non-dwarf LSB galaxies the rate of current star formation within the wide range of radial distances appears to be higher compared to the outer disks of most of HSB galaxies at similar values of the surface gas density. The factors that could stimulate the compression of the rarefied gas at the periphery of galaxies are briefly discussed. Attention is drawn to the idea that the densities of LSB disks estimated from their brightness may be underestimated.

arXiv comment7 pages, 3 figures

References in corpus (10)

• The Star Formation Efficiency in Nearby Galaxies: Measuring Where Gas Forms Stars Effectively
• Regulation of Star Formation Rates in Multiphase Galactic Disks: a Thermal/Dynamical Equilibrium Model
• A Search for Extended Ultraviolet Disk (XUV-disk) Galaxies in the Local Universe
• The Star Formation Law at Low Surface Density
• The Bluedisks project, a study of unusually HI-rich galaxies: I. HI Sizes and Morphology
• The HIX galaxy survey II: HI kinematics of HI eXtreme galaxies
• Observational insights on the origin of giant low surface brightness galaxies
• Massive Disks in Low Surface Brightness Galaxies
• UGC 1378 -- a Milky Way-sized galaxy embedded in a giant low-surface brightness disc
• On the gravitational stability and mass estimation of stellar disks